1. Field of Invention
The invention relates, generally speaking, to aids for the blind and in a more particular sense to walking aids in which the detection of obstacles, depressions, steps, and the like is effected mechanically, with a feeler or sensing device being caused to move from a normal position in such fashion as to actuate electrical means for alerting the user.
2. Description of the Prior Art
The prior art as known to me includes the following U.S. Pat. Nos.:
______________________________________ G. J. Vaughan 1,527,239 F. Murphy 1,177,582 O. E. Edstrom 2,379,426 G. B. Dusinberre 2,445,942 R. J. Kinney 2,683,461 R. C. Reel 3,158,162 C. C. Hagood, Sr. 3,223,099 C. O. Croker 3,251,371 ______________________________________
Prior art such as represented by the above listed patents has failed to offer a complete solution to the problems encountered by the blind, in that those devices that are intended to offer maximum assistance have in general been excessively complex and hence expensive. Alternatively, devices as heretofore conceived have failed to include means for sensing all the objects or surface irregularities that a blind person would be likely to encounter while walking.
Thus, wheeled devices have been provided, as will be noted from certain of the above listed patents, but have failed to provide a particular combination of side sensors, and sensors of elevated objects, such as the bumpers of parked vehicles, etc. Further, the prior art, where it does show electromechanical means of the character described, fails to show a particular combination of power source, switches, and alarm devices in which mechanical devices actuate electrical circuitry that extends through the rollable platform, tubular push-bar, and handle of the aid while still permitting normal one-hand operation of the device by the user.